you can give the candy to whoever you want to, but you dont have to give it to everyone. if some asshole comes to your door with a lame costume or no costume at all, tell him to give you candy instead...if he doesnt, just close your door on him.
'I was in the waiting room of my doctor's office before a physical this morning. There's nothing wrong with me, but healthy people get physicals just-for-the-hey-of-it every couple of days. When they finally mispronounced my name, I got up and walked down a hall with a nurse. After a while, the doctor came in and inspected my holes. He said that I should lose weight and consider stop smoking. I blew smoke in his face and explained that he is a douche bag. We all had a good laugh and he agreed.' -Skydaddy